UNIT 1.1: Whole numbers
LEARNING AIMS
After you have completed Unit 1, you must be able to do the following:
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Know what even numbers and uneven numbers are.
Know what will happen when you add even and uneven numbers.
Identify place values.
Break up numbers using expanded notation.
Round off to the nearest 5, 10, 100 and 1 000.

REVISION OF GRADE 5
Recognise and represent numbers so that it can be described and compared.
74 383
74 383

Lesson 1.1: Whole numbers
IMPORTANT
Whole numbers and counting numbers mean exactly the same. It is just
another name, just like for example plus, count and add up, which all have
the same meaning.
When we start counting, we count from 0. That’s why we talk about counting
numbers when we start counting at 0.
When you speak, you don’t say you have “zero” apples. It doesn’t sound
natural. You say you have no apples. Therefore we talk about natural
numbers when we start counting at 1.
A whole number can be an even number or an uneven number.
Even numbers
Even numbers always end on 2, 4, 6, 8 or 0.
An even number is divided by 2 and can be divided into equal parts without a
fraction.
For example: 8 ÷ 2 = 4
Uneven numbers
Uneven numbers always end on 1, 3, 5, 7 or 9.
An uneven number cannot be divided by 2.
If you divide uneven numbers by 2, you get fractions.
For example: 7 ÷ 2 = 3,5

Expanded notation
There are three ways in which a number can be written in expanded notation
or expanded form.
For example:
35 974
1.
30 000 + 5 000 + 900 + 70 + 4
2.
(3 × 10 000) + (5 × 1 000) + (9 × 100) + (7 × 10) + (4 × 1)
3.
3TTh + 5Th + 9H + 7T + 4U
Rounding off
Rounding off means that a number is taken to the nearest 10, 100 or 1 000.
To the nearest 10
When a number ends on 1, 2, 3 or 4, it goes to the previous number.
When a number ends on 5, 6, 7, 8 or 9, it goes to the next number.
For example:

To the nearest 100
When a number of the Tens ends on 2, 3 or 4, it goes to the previous
number.
When a number of the Tens ends on 5, 6, 7, 8 or 9, it goes to the next
number.
For example:

Even number + even number = even number
Even number + uneven number = uneven number
Uneven number + uneven number = even number
15

equal to
greater than
less than
not equal to
almost equal to
and
two-dimensional shape
three-dimensional object

16

Study Guide 1/2
G06 ~ Mathematics

Unit

1.1

Lesson 1.2: Whole numbers
Counting, ordering, comparing, representing and place value
Mental maths 1
You have to do mental maths every day. Work as quickly and correctly as
possible. Only write down the answers.
1.